Wireless networks are increasingly employed to provide various communication functions including voice, video, packet data, messaging and the like. A wireless network such as a wireless local area network (WLAN) in a conventional infrastructure configuration comprises a number of nodes, which may include any number of access points (APs) and any number of stations (STAs). Each AP may act as a coordinator for communication with the STAs.
A functional limitation of any WLAN is the transmission and reception range of the AP. For example, the approximate indoor range of a WLAN employing the IEEE 802.11n protocol is 70 m, and may be significantly reduced depending upon the physical environment. Therefore, in order to increase the area served, it may be desirable to extend the range of the WLAN. To accomplish this, a device such as a bridge, having AP-like functionality, may be connected to the network. It may also be desirable for the bridge to be connected wirelessly to avoid the need for cabling. This configuration is analogous to having two (or more) APs that communicate with each other wirelessly, each capable of associating with one ore more client stations (STAs).
IEEE 802.11 standards make certain provisions for the use of wireless bridges in the form of a wireless distribution system (WDS). Under these standards, two or more physically separated APs coordinate operation, such that any STA, or other network node, within range of either AP may communicate over the WLAN. To achieve this functionality, under the 802.11 standards, the header of each frame exchanged over the WLAN includes four distinct addresses, the receiver address, the transmitter address, the destination address and the source address. Provided that the participating APs are configured to properly interpret and process each of the addresses, the use of WDS as specified by 802.11 allows the range of the WLAN to be extended in the intended manner. APs having this capability are termed herein four address (4A) compatible.
However, the provision of four addresses in the frame header is a relatively recent introduction. As such, many currently deployed APs are not 4A compatible, and are termed herein legacy APs. These legacy APs are unable to provide WDS functionality using the mechanisms established by 802.11 standards. Accordingly, even if the bridge device being added to the WLAN is 4A compatible, the presence of any legacy APs that do not have this capability may prevent the intended operation of the WLAN.
Therefore, there remains a need to provide systems and methods for extending the range of a WLAN using a bridge that is compatible with legacy APs. Similarly, there is a need for providing such capabilities without using frame headers that specify four addresses. This invention accomplishes these and other goals.